Summary: Nuclear Physics B331 (1990) 263-276
North-Holland
WORMHOLES WITH A PAST*
L.F. ABBOTT
Physics Department, Brandeis University, Waltham, MA 02254, USA
Edward FARHI**
Physics Department, Brandeis University, Waltham, MA 02254, USA
and
Lyman Laboratory of Ptzvsies, Harvard University, Cambridge, MA 02138, USA
Received 28 June 1989
We discuss Minkowski space interpretations of euclidean solutions which provide semiclassi-
cal approximations to quantum processes. In particular, we consider wormhole and euclidean
bounce solutions. We argue that the semiclassical description involves an instantaneous disconti-
nuity in the Minkowski signature classical evolution and that the euclidean solutions provide final
and initial value data on either side of this discontinuity. In the case of the de Sitter wormhole
and bounce solutions, we resolve the problem of having a single maximal surface on the
euclidean solution which must provide both past and future data across the Minkowski signature
discontinuity.
1. Introduction
Although as physicists we frequently compute in euclidean space, we live in